Previously liquid level control and flush diaphragm-type valves employed in tanks, such as flush tanks for toilets, had diaphragms with small holes through the diaphragms as the bypass for pressurizing the chambers on the opposite sides thereof, which holes readily and often became clogged, thus defeating the proper operation of these valves, particularly if the water contained salts which on standing formed precipitates that clogged the small holes in these diaphragms. Such diaphragms are shown in Criss U.S. Pat. No. 2,283,973 issued May 26, 1942 and Layton U.S. Pat. No. 2,318,236 issued May 4, 1943, both found in Class 137-Subclass 444.
Ball-type valves previously had their balls confined within chambers to insure their proper seating and not free to move throughout the chambers, and no ball-type valves have been found to be employed in chambers in which one wall was a flexible diaphragm. Furthermore, such balls were usually made of metal or material denser than the fluid they were surrounded by and to control, and they seated against flexible or resilient gaskets. Thus their action was relatively sluggish. Examples of such ball valves in fluid tank level control valve mechanisms are shown in the following U.S. patents: Pinaire U.S. Pat. No. 2,588,869 issued Mar. 11, 1952 and Crockett U.S. Pat. No. 2,608,991 issued Sept. 2, 1952, both found in Class 137-Subclass 413; and Reaves U.S. Pat. No. 2,738,801 issued Mar. 20, 1956 found in Class 137-Subclass 449. No one of these patents shows a valve having both a ball and a diaphragm, not to mention a ball in the chamber having one wall formed by the diaphragm, nor are their balls free to move through relatively large chambers, but instead are confined to chambers having diameters less than about twice the diameters of the balls.